Cartridge feeding mechanism for the magazines of automatic firearms



May 13, 1952 o. SCHALKLI 2,596,293

CARTRIDGE FEEDING MECHANISM FOR THE MAGAZINES OF AUTOMATIC FIREARMS Filed Nov. 29, 1947 INVENTOR: 0&0 Sc/mZ/(lc' Patented May 13, 1952 UNITED STATS r QFFICE CARTRIDGE FEEDING MECHANISM FOR THE MAGAZINES OF AUTOMATIC FIREARMS Otto Schiilkli, Zurich, Switzerland, assignor to Machine Tool Works Oerlikon, Administration Company, Zurich-Oerlikon,

Swiss company Switzerland, a

Application November 29, 1947, Serial N 0. 788,890 In Switzerland November 2'7, 1946 Section 1, Public Law 690, August 8, 1946 Patent expires November 27, 1956- 1 Claim.

In automatic fire arms the cartridges are, as a rule, fed out of magazines set up on the weapon, or they are inserted in belts conveyed to the weapon. Cartridge feeding, however, involves certain difficulties owing, for instance, on the one hand, to the substantial weight of each individual cartridge in weapons using ammunition of 20 mm. or larger size, and, on the other hand, to the rate of fire in modern weapons being close to, or even reaching, 1000 rounds per minute, so that substantial power is required to ensure the acceleration and regular feeding of the individual cartridges within the available time.

In cartridge feeding from magazines the individual cartridges are pushed towards the outlet by a spring which is pretensioned when the magazine is being filled. Practice has shown, however, that the spring pressure exerted on the cartridges is not sufiicient to accelerate and feed all the cartridges within the time available during the excess breech block travel and the consequent opening of the feeding aperture. This occurs chiefly at high firing rates. On the other hand, belt feeding has not proved satisfactory for ammunition of 20 mm. and more, since in this case also the belt drive requires substantial power.

The present invention provides a cartridge feeding mechanism for automatic fire arms, in which the cartridges are piled up in a magazine and. are under the action of a power source which exerts pressure on the cartridges towards the magazine outlet, measures being provided to ensure the regular feeding of the cartridges even at maximum firing rates. According to the present invention, these measures provide for a feeding appliance which is located close to the magazine outlet and is under the pressure of an additional power source. By way'of example, the feeding appliance may be actuated by a spring which is tensioned when the magazine is being filled, or electricalmeans, for instance an electromotor or electro-magnets, maybe provided for this purpose. The feeding appliance can suitably consist of a star-shaped member adapted to engage the cartridges.

The accompanying drawing shows one constructional form of the invention by way of example.

On the drawing:

Figure 4 shows the magazine outlet in section, the breech block being in its rearmost position; and

Figure 5 is a view similar to Figure 4 when the breech block has moved forwards from its rearmost position to uncover the outlet.

In known manner, the cartridges 2 are arranged in a channel 3 of the magazine I, the filling of which is effected in the usual manner. The feeder or follower 4 is under the pressure of a spring 5 and engages behind the rearmost cartridge, being tensioned when the cartridges are introduced into the magazine. The channel 3 which is spiral or worm-shaped is completely filled with cartridges. A star-shaped member 6 is fitted close to the magazine outlet and is connected by a pinion l with a toothed wheel 8, mounted on the same shaft as a spring 9 which, as a result of the rotation of the star-shaped member 5, is tensioned as and when the cartridges are introduced into the magazine. At the magazine outlet locking pawls ID are fitted.

The operation of the mechanism described above is briefly as follows:

In the constructional example shown the last three cartridges are pushed forward by the starshaped member 6, driven by the spring 9, as soon as a, cartridge is introduced into the cartridge chamber, and the breech block has travelled rearward to such an extent as to leave the feedin opening free. It is obvious that the spring 9 has no difficulty in accelerating the required three cartridges even in the shortest time, thus ensuring even at maximum firing rate that the cartridges shall be quickly and reliably fed. In order to bring up the other cartridges piled. up in the magazine a time interval remains in which the magazine spring 5 is easily able to bring up all cartridges piled up on top of one another.

It goes without saying that the feeding means, which in the constructional example are represented by a star-shaped member, need not in all circumstances be driven by a spring 9. As already mentioned, the driving power can also be supplied by electrical means, for instance an electro-motor or electro-magnets. The feeding of the cartridges piled up in the magazine can also be effected by the said electrical means, instead of by a spring.

The use of the device according to the present invention eliminates the difficulties referred to, above. Indeed, the fact that even at the maxi. mum firing rate onl a few cartridges have to be accelerated in the short time interval available.

3 ensures in all cases reliable feeding of the cartridges.

I claim:

A cartridge-feeding device for automatic firearms, comprising, in combination, a magazine having a spiral passage formed therein for the cartridges, a spring-tensioned follower located within said magazine at the. inner end of said passage and adapted to eject said cartridgesout of the outer end of said passage, the tension of said follower feeding all of said cartridges to said outer end, a separate cartridge-shifting device located in said magazine adjacent said outer end and adapted to engage cartridges-adjacent said outer end to accelerate the ejection thereof, and a separate spring connected; with said car; tridge-shifting device to operate said cartridge,- shifting device and thereby accelerate the removal of the cartridgesfrom said passage.

OTTO SCI-IALKL I.

4 REFERENCES CITED The following references. are of record in the file of this patent:

UNITED STATES PATENTS 

